Say, "No," over and over. Be sure to vary the sound of each no, and keep an even tempo even as they’re trying to speak. Maybe sing a song with all "No’s" This is the most fun if you can keep going until they hang up.
If they want to loan you money, tell them you just filed for bankruptcy and you could it. Ask, "How long can I keep it? Do I have to ever pay it back, or is it like that other money I borrowed before my bankruptcy?"
If they start out with, "How are you today?" say, "Why do you want to know?" Or you can say, "I’m so glad you asked, because no one seems to care these days and I have all these problems, my colon is acting up again, my rectum are sore, my pet rock just died…" When they try to get back to the sales process, just keep talking about your problems… if they persist - ask them why they don’t care.
If the person says he’s Joe Shmoe from the Acme Company, ask him to spell his name, then ask him to spell the company name, then ask for his address. Ask for landmarks. Continue asking questions about the company for as long as necessary.
This one works better if you are male: Telemarketer: "Hi, my name is Jessica and I’m with Roger Dodd Services…. You: "Hang on a second." (few seconds pause) "Okay, (in a really husky voice) what are you wearing?"
If you get one of those pushy sales people who just won’t shut up, patiently listen to their sales pitch. When they try to close the deal, tell them that you’ll need to go get your credit card. Then, just set the phone down and go do laundry, go shopping or whatever. See how long that commission based scum waits for you to get your credit card.
If a long distance phone company calls trying to get you to sign up for their Family and Friends plan, reply, in as sinister a voice as you can, "I don’t have any friends… would you be my friend?" If that doesn’t work, say "Please."
Tell them you work for the same company they work for. For example: Telemarketer: "This is John From Acme Sales."
You: "Acme Sales, hey I work for them too! Which center are you calling from?"
Telemarketer: "Uh, Dallas, Texas."
You: "Great, how’s business over there? The weather? Too bad the company has a policy against selling to employees! Oh well, see ya."
Let the person go through their spiel, providing minimal but necessary feedback in the form of an occasional "Uh-huh, really, or, "That’s fascinating." Finally, when they ask you to buy, ask them to marry you. They get all flustered, but just tell them you couldn’t give your credit card number to someone who’s a complete stranger. You might even find your soulmate.
Tell the telemarketer (this is my personal favorite) you are busy and if they will give you their phone number you will call them back. If they say they are not allowed to give out their number, then ask them for their home number and tell them you will call them at home (this is usually the most effective method of getting rid of telemarketers). If the sales person says, "Well, I don’t really want to get a call at home," say, "Ya! Now you know how I feel."